Many hail Deadmau5 as "my fave DJ!" Some refer to the King Rat as the "Troll of Trolls." Others whisper "asshole."

For years, Joel Zimmerman, the human who wears that famous rodent helmet for a living, has been cultivating a reputation (mainly via Twitter) as a perpetual, unrelenting jerk. He might bitch about the price of tickets for his own club gigs. And he might slander any and every EDMer for any and every reason. And he will certainly sneer at the suggestion that he should be overly nice to someone just because that guy's undergone gallbladder surgery.

So last night, as the Mau5 took Ultra Music Festival 2014's main stage in place of the ailing Avicii, it was probably inevitable that he'd piss off a lot of people.

As far as Deadmau5 sets go, it was fairly typical: moody, erratically paced, and self-indulgent, though still offering a few moments for the mainstream fans. And the ravers seemed to be OK with the goings-on, even if they weren't exactly going wild.

But it wasn't just the headliner that'd caused the vibe to be so muted. All evening, it had been raining, on and off. The crowd had thinned out, as many partiers fled for their hotels and homes when the downpour was at its worst. Even the Mau5heads who'd stuck 'round were looking wet and worn-out.

He played some remixes, like Morgan Page's "Longest Road." He played some originals, like "Suckfest 9001," "Drop the Poptart," "Fn Pig," and "The Veldt." And he even played some stuff like Martin Garrix' "Old McDonald"-merking "Animals," of which the King Rat said, "I fuckin' love that track."

But the flash point of the night ended up being a mashup: Mr. Mau5's own "Ghosts 'n' Stuff" and Avicii's "Levels."

One member of the Ultra crowd said, "Oh, no. He didn't." And incidentally, Tiësto seems to have felt the same way. Even if the reaction was a bit delayed.

Though initially commending the Mau5 for honoring Avicii with a setlist shoutout (tweeting, "I love the fact that he supports his EDM colleagues!!"), Tiësto quickly shifted his perception of the "Ghosts 'n' Stuff" vs. "Levels" moment when he was tipped off that maybe, just maybe it was meant as a caustic crack of some kind.

The King Rat's response: "How does one play a track sarcastically?" and a string of dismissive tweets that he's since deleted.

Of course, though, Tiësto wasn't the only person who the Mau5 managed to piss off.

By the end of his set (which admittedly wound down without the figurative fireworks accompanied by real fireworks that ravers at UMF expect), he'd also disappointed entire clusters of festival-goers who loudly claimed that they'd bought their tix just to see Avicii.

These people were everywhere. But they certainly weren't the majority. They were just the loudest. Even on Twitter.

And last night, as the King Rat left Ultra main stage, he delivered one last jab, fussing: "Now how am I gonna get down? I'm gonna fall on my ass and end up in a hospital bed between Afrojack and Avicii."